Speaking of doctors, Jason Robards also played one in the film adaptation.
Backed by the Pentagon: Almost. They had to get by with using footage from the documentary First Strike after the military backers insisted it be made clear that the Soviets had started the war. Meyer naturally refused, as a big part of the film's message was that it didn't matter who fired first; everyone would still be dead. A more practical reason is suggested by Threads a Soviet first strike would most likely happen in the early morning hours. A nuclear strike at three in the morning would cause difficulties in filming it. Not enough light... well, for about thirty minutes.
Dawson Casting: Steve Guttenberg looks older than his 25 years, but his character Stephen Klein is only nineteen.
The Danza: Steve Guttenberg's character is also named Steve.
Executive Meddling: ABC censors severely toned down numerous graphic scenes in order to reduce the body count of corpses and severe burn victims.
Many European viewers assumed that the relatively low body count (and the lack of decomposition, skeletal remains, etc.) was due to American naivete about the effects of war, especially since the movie was shown theatrically in Europe and not on television.
One change, to the last scene, had Russell Oakes finding his wife's watch on the ground in the remains of their home. In the original, he was supposed to find her watch with her skeletal remains.
According to an early draft of the script, the attack sequence was longer and supposed to have VERY graphic, yet very accurate, shots of what happens to a human body during a nuclear blast, with people being set on fire, their flesh carbonizing, eyes melting, faceless faces, and skin hanging; similar to what happened in Hiroshima. Unfortunately, there was no way any of this could have been allowed on national TV.
Also, in the same early draft, the attack sequence was supposed to be done with miniatures and models instead of stock footage, but budget and time constraints forced them to use the latter.
Nicholas Meyer vowed never to work in TV again due to all the meddling.